Injection fluid quantification

ABSTRACT

Methods and systems may quantify how much contrast fluid is injected into a patient by a powered fluid injector. A controller of the powered fluid injector can receive a command from a user to begin dispensing contrast fluid. The controller may determine whether a hemodynamic pressure signal is present from a pressure sensor in fluidic connection with the vasculature of the patient. The powered fluid injector may dispense a quantity of contrast fluid in response to the command. The controller may add the quantity of contrast fluid to an injection quantity if the hemodynamic pressure signal is present just prior to and/or just after the quantity of contrast fluid is dispensed. The controller may refrain from adding the quantity of contrast fluid to the injection quantity if the hemodynamic pressure signal is not present just prior to and/or just after the quantity of contrast fluid is dispensed.

TECHNICAL FIELD

This application relates generally to the field of medical injectiontechnology and, more particularly, to devices and methods forquantifying the amount of fluid that has been injected into a patient.

BACKGROUND

Many medical imaging procedures, such as angiography, involve injectinga contrast fluid into a patient. Angiography is a procedure used in thediagnosis and treatment of cardiovascular conditions, includingabnormalities or restrictions in blood vessels. During angiography, aradiographic image of the heart or vascular structure is obtained byinjecting contrast fluid through a catheter into the vasculature (e.g.,the coronary artery) of the patient. The injected contrast fluid canpass to vascular structures in fluid communication with the blood vesselin which the injection is made. X-rays are passed through the region ofthe body in which the contrast fluid was injected. The X-rays areabsorbed by the contrast fluid, causing a radiographic outline or imageof the vasculature containing the contrast fluid. Contrast injection canbe used in conjunction with other medical procedures as well, such asoptical coherence tomography (OCT) imaging, intravascular ultrasound(IVUS) imaging, computed tomography (CT) imaging, magnetic resonanceimaging (MRI), and interventional device procedures/placements.

A powered fluid injector can be utilized to inject amounts of thecontrast fluid into the patient during such medical procedures. However,conventional powered fluid injectors are unable to quantify how muchcontrast fluid is actually injected into the patient. For instance,contrast fluid may be dispensed from the powered fluid injector for avariety of reasons (e.g., to purge fluid lines, to perform a wet connectof system components, to prime the powered fluid injector for use)without ever entering the patient's vasculature. Thus, a user (e.g., aphysician) using a conventional powered fluid injector is left toapproximate the amount of contrast fluid injected into the patient.

SUMMARY

Embodiments disclosed herein quantify how much fluid that is dispensedfrom a powered fluid injector is actually injected into a patient ratherthan used for other non-injection purposes. Some embodiments determinewhether dispensed fluid was injected or not based on whether an invasiveblood pressure sensor detects a hemodynamic pressure signal (injected)or not (not injected) in temporal proximity to when the fluid wasdispensed. A quantity of dispensed fluid that is determined to have beeninjected into a patient is added to an injection quantity, while aquantity of dispensed fluid that is determined not to have been injectedinto a patient is not added to the injection quantity. Calculating theinjection quantity in this manner provides an objective measurement ofhow much of the dispensed fluid was injected into the patient as opposedto being used for other purposes. Such an objective measurement issuperior to a user estimating how much dispensed fluid was used fornon-injection purposes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a powered fluidinjector.

FIG. 2A is a flowchart of an illustrative method for dispensing acontrast fluid and/or a non-contrast fluid as part of an injectionprocedure.

FIG. 2B is a flowchart of an illustrative method for quantifying howmuch contrast fluid dispensed by a powered fluid injector is injectedinto a patient vs. not injected into the patient.

FIG. 2C is a flowchart of an illustrative method for quantifying howmuch non-contrast fluid dispensed by a powered fluid injector isdispensed into a patient vs. not dispensed into the patient.

FIG. 3 is a flowchart of an illustrative method for determining whetherto take an injection action based on whether a hemodynamic pressuresignal is present from an invasive pressure sensor.

FIG. 4 is a flowchart of an illustrative method of operating a systemthat includes a powered fluid injector.

DETAILED DESCRIPTION

The following detailed description is exemplary in nature and providessome practical illustrations and examples. Those skilled in the art willrecognize that many of the noted examples have a variety of suitablealternatives.

A number of various exemplary flow measurement techniques are disclosedherein using the description provided as follows in addition to theaccompanying drawings. Each of the techniques disclosed herein can, insome examples, be employed independently or in combination with one ormore (e.g., all) of the other techniques disclosed herein.

FIG. 1 illustrates a perspective view of an exemplary embodiment of apowered fluid injector 100. In operation, the powered fluid injector 100can inject a quantity of fluid into a patient, for instance into avessel of a patient via a catheter. The fluid injected by the poweredfluid injector 100 can be, for example, a contrast fluid, a non-contrastfluid (e.g., saline), or a combination thereof. By injecting a quantityof fluid into a patient, the powered fluid injector 100 can facilitate avariety of medical diagnostic and/or interventional procedures,including the collection of image data representing an anatomical regionof interest. These procedures can include, as examples, opticalcoherence tomography (OCT) imaging, intravascular ultrasound (IVUS)imaging, computed tomography (CT) imaging, magnetic resonance imaging(MM), angiographic procedures, and interventional deviceprocedures/placements.

The illustrated powered fluid injector 100 includes a drive assemblyhousing 102 and a sleeve 104. The sleeve 104 can be secured to the driveassembly housing 102. For example, the drive assembly housing 102 caninclude an opening, and the sleeve 104 can be secured to the driveassembly housing 102 at or near such opening. The sleeve 104 may extendout from the drive assembly housing 102 and may be configured to receiveand hold a reservoir 106. The reservoir 106 can have an internalreservoir volume containing a fluid and can include a plunger 108 withinthe internal reservoir volume. At least a portion of a drive assemblycan be housed within the drive assembly housing 102.

The drive assembly can be configured to pressurize fluid within theinternal reservoir volume. For instance, the drive assembly may coupleto the plunger 108, such as at the opening in the drive assembly housing102, and drive the plunger 108 within the internal reservoir volume. Asthe plunger 108 is progressively driven within the reservoir 106, fluidwithin the internal reservoir volume can be output from the reservoir106 along tubing 109 leading to a catheter 126 that is inserted into apatient's blood vessel to inject the fluid into the vasculature. Incertain applications of the powered fluid injector 100, output fluid,such as contrast media, can be pressurized anywhere from 1000-1500 psi(e.g., 1200 psi).

The illustrated embodiment of the powered fluid injector 100 includesseveral features that can be useful in pressurizing and delivering fluidduring operation. The powered fluid injector 100 can include acontroller 110. The controller 110 can include a user interface forvarious operational aspects. For example, the controller 110 can beutilized by a user to set up various parameters and/or protocols to beused for a given fluid injection procedure. In one example, the user caninteract with the controller 110 to input fluid injection parameterssuch as flow rate, injection volume (e.g., maximum), injection pressurelimit (e.g., maximum), fluid injection duration, rise time, and/or otherinjection parameters. In one embodiment, the controller 110 includes atouch-screen panel display, enabling a user to view and modify injectionparameters. The controller 110 can also be used to initialize thepowered fluid injector 100 (e.g., to prepare it for a patient fluidinjection), or to activate certain features or sequences of operation.The controller 110 may also provide status information, includinginformation related to past or currently ongoing injection procedures aswell as any appropriate alerts. The controller 110 can include animaging engine having one or more processors for controlling operationof the powered fluid injector 100. Such processors can also controlother components, such as the drive assembly, a peristaltic pump 112,when present, and/or any sensors and detectors included at the poweredfluid injector 100.

In addition to the controller 110, the illustrated powered fluidinjector 100 includes a hand-control device 113 for user input. Thehand-control device 113 can be coupled to the controller 110 eitherwirelessly or via a lined connection. Although in other embodiments, thehand-control device 113 can be connected to a component of the poweredfluid injector 100 other than the controller 110, such as drive assemblyhousing 102. The hand-control device 113 can generate and send varioussignals related to an injection procedure to the controller 110 or otherconnected component. A user can actuate one or more interface componentsat the hand-control device 113 to control an injection procedure. Forexample, the user can use hand-control device 113 as a variable-ratecontrol device to alter the fluid flow rate output from the poweredfluid injector 100 and/or as a mechanism for starting or stopping afluid injection.

The powered fluid injector 100 can also include one or more componentsuseful for supplying fluid to be used in an injection procedure. Acontainer 114 can include a supply of fluid, such as contrast media, andbe secured to a holder 116 at the powered fluid injector 100. Fluid fromthe container 114 can be supplied to the reservoir 106 for use during aninjection procedure. For example, fluid from the container 114 can bedrawn into the reservoir 106 when the plunger 108 is being retracted(e.g., moved in a direction toward the drive assembly housing 102) andthereby refill the internal reservoir volume. Similarly, when thepowered fluid injector 100 includes the peristaltic pump 112, a secondcontainer 118 can include a supply of fluid, such as a flushing medium(e.g., saline), and be secured to a holder 120 at the powered fluidinjector 100. When present, the peristaltic pump 112 can receive fluidfrom the second container 118 and deliver such fluid to the patient.Often times, the peristaltic pump 112 may be used to delivernon-contrast fluid, such as saline, at a lower pressure than that atwhich the drive assembly delivers contrast fluid from the reservoir 106.A valving system 124 can be included to selectively place the reservoir106 or peristaltic pump 112 in communication with the patient.

As described elsewhere herein, the controller 110 of the powered fluidinjector 100 may control various functions of the powered fluid injector100, which may include dispensing contrast fluid out through tubing. Insome embodiments, the controller 110 may be housed in a housing of adisplay device. In some embodiments, the controller may be housed in theinjector housing.

The powered fluid injector may be connected to a catheter 126, fluidlyand electrically, that is inserted into a blood vessel (e.g., thecoronary artery) of a patient. When so connected, the powered fluidinjector can inject contrast fluid or dispense non-contrast fluid intothe patient's vasculature via the injector tubing and the catheter 126.In many embodiments, the catheter 126 may include an invasive bloodpressure sensor. The blood pressure sensor may be in electricalcommunication with the controller when the powered fluid injector isconnected to the catheter 126. The blood pressure sensor may provide ablood pressure signal to the controller when the catheter 126 is influidic connection with the powered fluid injector and may not provide ablood pressure signal when the catheter 126 is not in fluidic connectionwith the powered fluid injector.

FIGS. 2A-2C illustrate a method 200 for quantifying the amount of fluid(contrast fluid and/or non-contrast fluid) that has been injected, viathe powered fluid injector, into a patient during an injectionprocedure. An injection procedure may begin 210 with such steps aspreparing the injection equipment and making sure the patient is fullyprepared. In many instances, an injection procedure is one of multipleprocedures being performed on a patient as part of a medicalintervention. The catheter that is inserted into the patient's bloodvessel may be accessed by equipment other than the powered fluidinjector for performing various other procedures on the patient. In someinstances (e.g., in a cardiac catheterization lab), there may bemultiple injection procedures interspersed among other procedures in amedical intervention.

At various instances, contrast fluid may be dispensed from the poweredfluid injector that is not injected into the patient. For example, thepowered fluid injector may dispense contrast fluid into a wastereceptacle or onto a surgical table (not into a patient's blood vessel)when purging all air bubbles from the system. Such purging may occur anytime air must be removed from the line (e.g., cavitation, badconnection, initial setup, changing catheters (e.g., diagnostic tointerventional), adding microcatheters for an intervention, etc.). Insome instances, users may flush first with saline and then with contrastfluid. In another example, a user may dispense contrast fluid to drivesaline out of the injector tubing (e.g., if the tubing was filled withsaline to improve the hemodynamic pressure signal). In another example,a user may cause the powered fluid injector to dispense a small amountof contrast fluid to facilitate a wet connection between two componentsof an injection system (e.g., injector tubing to the catheter that isinserted into the patient's blood vessel, stopcock to pressure line,stopcock to catheter, etc.). In another example, a user may otherwisetest the system (e.g., for leaks) by dispensing contrast fluid into awaste receptacle or onto a surgical table (not into a patient's bloodvessel). For similar purposes, non-contrast fluid may be dispensed fromthe powered fluid injector not into a patient's vasculature.

The controller may receive a command from a user (e.g., a cardiologist)to begin dispensing fluid 212 for an injection procedure (e.g., amedical imaging procedure). The user may provide the command to thecontroller via a hand controller, via a touchscreen, or via anothersuitable input device. In some instances, the command may be automatedthrough the injector. The controller may determine whether the user'scommand was to begin dispensing contrast fluid or non-contrast fluid214. FIG. 2B illustrates one embodiment of what the controller may do ifthe command was to begin dispensing contrast fluid. FIG. 2C illustratesone embodiment of what the controller may do if the command was to begindispensing non-contrast fluid.

The controller may determine how much of the fluid that was dispensedwas actually delivered through a catheter into the patient's bloodvessel. The controller may measure the quantity of fluid that wasdelivered into the patient's vasculature rather than relying on a user'sestimate of how much of the total dispensed fluid was not delivered intothe patient's vasculature.

To determine whether a specific quantity of fluid is delivered into apatient's vasculature or not, the controller may determine whether ahemodynamic pressure signal is present from an invasive pressure sensorin fluidic connection with the patient's vasculature. As noted, in someembodiments, the pressure sensor may be in fluidic connection with thecatheter that is positioned within the patient's vasculature. In someembodiments, the catheter may be a guide catheter. In some embodiments,the catheter may be a diagnostic catheter.

The pressure sensor may be configured to provide a hemodynamic pressuresignal to the controller only when the catheter is connected to andbrought into fluidic connection with the powered fluid injector'stubing. The pressure sensor is in electrical communication with thecontroller. When the preliminary steps of the injection procedure havebeen completed and the user is ready to deliver a quantity of fluid intothe patient's vasculature, the catheter that is positioned within thepatient's vasculature may be connected to and brought into fluidicconnection with tubing of the powered fluid injector. Before suchconnection, the pressure sensor may not provide a hemodynamic pressuresignal to the controller. After such connection, with the pressuresensor in fluidic connection with the patient's vasculature and inelectrical communication with the controller, the pressure sensor maydetect the patient's blood pressure and provide a hemodynamic pressuresignal to the controller. If the catheter is disconnected from thepowered fluid injector again, the pressure sensor may not provide ahemodynamic pressure signal because the pressure sensor is no longer influidic connection with the catheter.

In some instances, the controller may determine whether the hemodynamicpressure signal is present in close time proximity to when the poweredfluid injector begins dispensing fluid. For example, the controller maybe configured to determine whether the hemodynamic pressure signal ispresent before causing the powered fluid injector to begin dispensingthe quantity of fluid. In such examples, the controller may receive thecommand from the user to begin dispensing fluid and determine if thehemodynamic pressure signal is present before causing the powered fluidinjector to begin dispensing a quantity of fluid. According to someexamples, the controller may be configured to determine whether thehemodynamic pressure signal is present after causing the powered fluidinjector to cease dispensing the quantity of fluid. In such examples,the controller may receive the command from the user to cease dispensingfluid and cause the powered fluid injector to cease dispensing aquantity of fluid before determining if the hemodynamic pressure signalis present.

In some embodiments, the controller may determine whether thehemodynamic pressure signal is present within a predetermined amount oftime of when the powered fluid injector begins dispensing fluid. Thecontroller may be configured to determine whether the hemodynamicpressure signal is present within a predetermined amount of time (e.g.,20-30 milliseconds) of causing the powered fluid injector to dispensethe quantity of fluid. In some instances, the controller may beconfigured to determine whether the hemodynamic pressure signal ispresent within a predetermined amount of time before the controllercauses the powered fluid injector to begin dispensing the quantity offluid. In some instances, the controller may be configured to determinewhether a hemodynamic pressure signal is present within a predeterminedamount of time of the powered fluid injector completing dispensing ofthe quantity of fluid.

In some embodiments, the controller may determine whether a hemodynamicpressure signal is present multiple times during an injection procedure.In various instances, the controller may be configured to determinewhether a hemodynamic pressure signal is present within a firstpredetermined amount of time before the controller causes the poweredfluid injector to begin dispensing the quantity of fluid and within asecond predetermined amount of time of the controller causing thepowered fluid injector to cease dispensing the quantity of fluid. Insome instances, the controller may be configured to determine whether ahemodynamic pressure signal is present within a predetermined amount oftime of the powered fluid injector completing dispensing of the quantityof fluid. Making such determinations multiple times may confirm to theuser and/or controller that the catheter is actually connected to thepowered fluid injector and as such, may inhibit inaccurately tabulatingthe injection quantity. This feature may be especially helpful ininjection procedures that require dispensing fluid at multiple times.For instance, if there is a hemodynamic pressure signal present beforeand after dispensing the quantity of fluid, the controller may concludethat the fluid was delivered into the patient. If there is a hemodynamicpressure signal present before but not after or after but not beforedispensing the quantity of fluid, the controller may not conclude thatthe contrast fluid was delivered into the patient.

Referring to FIG. 2B, the controller may cause the powered fluidinjector to dispense a quantity of contrast fluid in response to theuser command 216. The controller may be configured to determine whethera hemodynamic pressure signal is present from the blood pressure sensor218. The controller may determine an injection quantity of contrastfluid that is actually injected into the patient based on whether ahemodynamic pressure signal is present in conjunction with thedispensation of contrast fluid. The controller may assess any pressuresignal received from the pressure sensor to determine if it has one ormore attributes consistent with those of a valid hemodynamic pressuresignal (e.g., a specific amplitude, a specific periodicity, etc.). Thecontroller may be configured to refrain from adding a quantity ofdispensed contrast fluid to an injection quantity if no hemodynamicpressure signal is present in temporal proximity to when the quantity ofcontrast fluid is dispensed. When no hemodynamic pressure signal ispresent in such instances, the controller may conclude that the quantityof contrast fluid was not injected into the patient 220 and may refrainfrom adding the quantity of contrast fluid to the injection quantity222. The controller may be configured to add the quantity of dispensedcontrast fluid to an injection quantity if a hemodynamic pressure signalis present in temporal proximity to when the quantity of contrast fluidis dispensed. When the hemodynamic pressure signal is present in suchinstances, the controller may conclude that the quantity of contrastfluid was injected into the patient 226 and may continue by adding thequantity of contrast fluid to the injection quantity 228. Thus, byadding or refraining from adding the quantity of dispensed contrastfluid to the injection quantity based on the presence of a hemodynamicpressure signal, the injection quantity may accurately reflect how muchcontrast fluid was actually injected into the patient.

As noted, in some examples, the controller may assess any pressuresignal received from the pressure sensor to determine if the pressuresignal constitutes a valid hemodynamic pressure signal. The controllermay assess the amplitude of the pressure signal (e.g., compare theamplitude with that of a typical hemodynamic pressure signal). Thecontroller may assess the periodicity of the pressure signal (e.g.,compare the periodicity with that of a typical hemodynamic pressuresignal). In some examples, the controller may assess both the amplitudeand the periodicity of the pressure signal.

The controller may be able to compare the injection quantity to apredetermined threshold to protect against injecting too much contrastfluid into a patient. As shown, the controller may determine whether theinjection quantity exceeds a predetermined threshold 230. Thepredetermined threshold may be based on complications associated withharmful amounts of the type of contrast fluid used in the injectionprocedure. Such complications may include Contrast Induced Nephropathy(CIN), associated with injecting too much contrast fluid into a patient.In some embodiments, the controller may be configured to notify the user(e.g., via the user interface) if the injection quantity exceeds thepredetermined threshold. When the injection quantity exceeds thepredetermined threshold, the controller may provide a notification 232.In some instances, when a notification occurs, the injection proceduremay end 234. In some instances, there may be multiple notificationsdepending on how close the injection quantity is getting to a level thatmight cause harm to a patient. In some embodiments, a user mayprogressively inject quantities of contrast fluid into the patient'svasculature during an injection procedure and be notified beforeinjecting undesired quantities of contrast fluid into the patient.

As shown, at different points during the injection procedure, the usercan determine whether or not to continue the injection procedure 224. Tocontinue the injection procedure, the user may again provide a commandto begin dispensing fluid to the controller (212 of FIG. 2A), and theprocedure can continue as described. To discontinue the injectionprocedure, for example, after imaging is complete, the user may end theinjection procedure 234 and not inject any more quantities of contrastfluid into the patient. When the injection procedure has ended 234, afinal injection quantity, corresponding to the total quantity ofcontrast fluid that was actually injected into the patient, can beprovided to the user and subsequently to the patient's medical record.

Referring to FIG. 2C, the controller may cause the powered fluidinjector to dispense a quantity of non-contrast fluid in response to theuser command 236. The controller may be configured to determine whethera hemodynamic pressure signal is present from the blood pressure sensor238. The controller may determine a dispensed quantity of non-contrastfluid that is actually dispensed into the patient based on whether ahemodynamic pressure signal is present in conjunction with thedispensation of non-contrast fluid. The controller may assess anypressure signal received from the pressure sensor to determine if it hasone or more attributes consistent with those of a valid hemodynamicpressure signal (e.g., a specific amplitude, a specific periodicity,etc.). The controller may be configured to refrain from adding aquantity of dispensed non-contrast fluid to a dispensed quantity if nohemodynamic pressure signal is present in temporal proximity to when thequantity of non-contrast fluid is dispensed. When no hemodynamicpressure signal is present in such instances, the controller mayconclude that the quantity of non-contrast fluid was not dispensed intothe patient 240 and may refrain from adding the quantity of non-contrastfluid to the dispensed quantity 242. The controller may be configured toadd the quantity of dispensed non-contrast fluid to a dispensed quantityif a hemodynamic pressure signal is present in temporal proximity towhen the quantity of non-contrast fluid is dispensed. When thehemodynamic pressure signal is present in such instances, the controllermay conclude that the quantity of non-contrast fluid was dispensed intothe patient 246 and may continue by adding the quantity of non-contrastfluid to the dispensed quantity 248. Thus, by adding or refraining fromadding the quantity of dispensed non-contrast fluid to the dispensedquantity based on the presence of the hemodynamic pressure signal, thedispensed quantity may accurately reflect how much non-contrast fluidwas actually dispensed into the patient.

The controller may be able to compare the injection quantity to apredetermined threshold to protect against injecting too muchnon-contrast fluid into a patient. As shown, the controller maydetermine whether the dispensed quantity exceeds a predeterminedthreshold 250. In some embodiments, the controller may be configured tonotify the user (e.g., via the user interface) if the dispensed quantityexceeds the predetermined threshold. When the dispensed quantity exceedsthe predetermined threshold, the controller may provide a notification252. In some instances, when a notification occurs, the injectionprocedure may end 254. In some instances, there may be multiplenotifications depending on how close the dispensed quantity is gettingto a level that might cause harm to a patient. In some embodiments, auser may progressively dispense quantities of non-contrast fluid intothe patient's vasculature during an injection procedure and be notifiedbefore dispensing undesired quantities of non-contrast fluid into thepatient.

As shown, at different points during the injection procedure, the usercan determine whether or not to continue the injection procedure 244. Tocontinue the injection procedure, the user may again provide a commandto begin dispensing fluid to the controller (212 of FIG. 2A), and theprocedure can continue as described. To discontinue the injectionprocedure, for example, after imaging is complete, the user may end theinjection procedure 254 and not dispense any more quantities ofnon-contrast fluid into the patient. When the injection procedure hasended 234, a final dispensed quantity, corresponding to the totalquantity of non-contrast fluid that was actually dispensed into thepatient, can be provided to the user and subsequently to the patient'smedical record.

In some embodiments, the controller may tabulate the injection quantityand/or the dispensed quantity in real time as fluid is being dispensedfrom the powered fluid injector. In some embodiments, the controller candetermine whether fluid is being delivered into a patient's vasculatureor not while the fluid is being dispensed from the powered fluidinjector (e.g., based on whether a hemodynamic pressure signal from theinvasive blood pressure sensor is present or not just prior to or justafter dispensation). In some embodiments, the controller may cause theinjection quantity and/or the dispensed quantity to be displayed to theuser in real time (e.g., via the user interface). The user may be ableto determine whether to continue delivering fluid into the patient'svasculature or not based on the displayed injection quantity and/ordispensed quantity. In some embodiments, the injection quantity and/orthe dispensed quantity, as well as the predetermined threshold, may bedisplayed to the user. In many embodiments, the controller mayautomatically exclude fluid that is not delivered into the patient fromthe injection quantity and/or dispensed quantity rather than requiringthe user to designate when fluid is not delivered into the patient(e.g., by pressing a purge button on the user interface). In someembodiments, the controller may provide an injection quantity capturinghow much contrast fluid has actually been injected into a patient'svasculature and a dispensed quantity capturing how much non-contrastfluid has actually been dispensed into the patient's vasculature. Insome such embodiments, the controller can provide running totals of suchquantities as fluid is being dispensed from the powered fluid injector.

The injection quantity and/or dispensed quantity may reset when amedical intervention for a patient is complete. In situations in whichthere are multiple injection procedures in a single medicalintervention, the injection quantity and/or the dispensed quantity mayreflect all the fluid of each kind that was delivered into the patient'svasculature in all the injection procedures during the medicalintervention (e.g., separate total injection and dispensed quantities).In some such instances, the injection quantity and/or the dispensedquantity may be broken down to reflect how much of each kind of fluidwas delivered in each of the injection procedures.

Controllers of injection systems discussed herein may cause the systemsto perform various functions. FIG. 3 shows a method 300 that thecontroller may cause the injection system to perform. In someembodiments, the injection procedure begins 310 in a manner similar tothose discussed elsewhere herein. The controller may receive a commandfrom a user to begin dispensing fluid (e.g., contrast fluid ornon-contrast fluid) 312. The controller may determine whether ahemodynamic pressure signal is present from the invasive blood pressuresensor 314. The controller may assess any pressure signal received fromthe pressure sensor to determine if it has one or more attributesconsistent with those of a valid hemodynamic pressure signal (e.g., aspecific amplitude, a specific periodicity, etc.). If the controllerdetermines that the hemodynamic pressure signal is indeed present, thecontroller may take an injection action 316. In many embodiments, thecontroller may take the injection action 316 only if a hemodynamicpressure signal is present from the invasive blood pressure sensor. Ifthe controller determines that no hemodynamic pressure signal ispresent, the controller may refrain from taking an injection action 318.

In different embodiments, the injection action can be an assortment ofdifferent actions. For example, in some embodiments, the injectionaction may include causing the powered fluid injector to dispense aquantity of fluid in response to the command to begin dispensing fluid.In such embodiments, the injection action may include adding thequantity of fluid to a counted quantity if the hemodynamic pressuresignal is present in temporal proximity to when the quantity of fluid isdispensed. In some embodiments, the controller may be configured tocompare the counted quantity of fluid that has actually been deliveredinto the patient's vasculature and to notify the user if the injectionquantity exceeds a threshold.

As noted elsewhere herein, in some embodiments, the controller mayconfirm that the catheter is inside the patient's vasculature and influidic connection with a pressure transducer that is connected to thepowered fluid injector both before and after dispensation of fluid. Thecontroller may be configured to determine whether the hemodynamicpressure signal is present from the invasive blood pressure sensor afterthe powered fluid injector has dispensed the quantity of fluid. In suchembodiments, the injection action may include adding the quantity ofdispensed fluid to the counted quantity only if the hemodynamic pressuresignal is present both before the quantity of fluid is dispensed andafter the quantity of fluid is dispensed.

Some powered fluid injectors include an air bubble detector that isconfigured to detect air bubbles in tubing that is connectable to thecatheter. Delivering such air bubbles to the patient can causesignificant adverse consequences. In such instances, the controller maybe configured to receive an air bubble signal from the air bubbledetector that an air bubble has been detected. In such embodiments, theinjection action may include preventing the powered fluid injector fromdispensing fluid based on the air bubble. In some embodiments, thecontroller may be configured to notify the user that he/she isattempting to purge the air bubble while the catheter is inside apatient's vasculature and in fluidic connection with the pressuretransducer.

In some instances, the controller may take additional actions afterpreventing the powered fluid injector from dispensing fluid based on theair bubble. For example, the user may disconnect the patient catheterfrom the powered fluid injector tubing and enter a second command topurge the air bubble from the powered fluid injector tubing. Thecontroller may receive the second command from the user to begindispensing fluid. The controller may then determine again whether thehemodynamic pressure signal is present from the invasive blood pressuresensor. The controller may cause the powered fluid injector to dispensea quantity of fluid to purge the air bubble in response to the secondcommand only if the hemodynamic pressure signal is no longer presentfrom the invasive blood pressure sensor.

As in other methods discussed herein, the method of FIG. 4 starts withbeginning an injection procedure 410. The powered injection system'scontroller may receive a command to begin dispensing fluid 412 (e.g.,contrast fluid or non-contrast fluid). Before the powered injectionsystem dispenses the fluid, the controller may determine whether thereis a hemodynamic pressure signal present from the invasive pressuresensor 414. The controller may assess any pressure signal received fromthe pressure sensor to determine if it has one or more attributesconsistent with those of a valid hemodynamic pressure signal (e.g., aspecific amplitude, a specific periodicity, etc.). If there is nohemodynamic pressure signal, the controller may infer that the patientcatheter is not connected to the powered fluid injector's patient tubingand that any fluid dispensed by the powered fluid injector will not bedelivered into the patient's vasculature. In such instances, thecontroller may cause the powered fluid injector to proceed withdispensing the requested fluid 416, but the controller may refrain fromadding the dispensed quantity of fluid to the quantity that is countedas being delivered into the patient's vasculature 418 (e.g., an injectedquantity of contrast fluid injected into the patient's vasculature or adispensed quantity of non-contrast fluid dispensed into the patient'svasculature).

If the controller receives the command to begin dispensing fluid 412 anddetermines that a hemodynamic pressure signal is indeed present from theinvasive pressure sensor 414, the controller may make one or moreadditional determinations before causing the powered fluid injector todispense fluid in response to the command. For example, the controllermay determine whether an air bubble signal is present from an air bubbledetector 420. In some instances, the user may take steps to purge one ormore air bubbles from somewhere the powered fluid injector, mistakenlythinking that the patient catheter is disconnected from the poweredfluid injector. If the user's command to begin dispensing fluid 412 wasfor purposes of purging an air bubble, the controller may automaticallydetect such a mistake and prevent the powered fluid injector fromdispensing fluid despite the user's command 422. In such instances, thecontroller may notify the user that he/she is trying to purge an airbubble while the patient catheter is in fluidic connection with thepowered fluid injector's tubing and that therefore the powered fluidinjector is not permitted to dispense fluid 424. If the controllerdetermines that no air bubble signal is present from the air bubbledetector 420, the controller may proceed to cause the powered fluidinjector to dispense a quantity of fluid in response to the command fromthe user 426.

In some embodiments, the controller may once again determine whether ahemodynamic pressure signal is present from the invasive pressure sensorafter the powered fluid injector has ceased dispensing fluid 428. Thecontroller may assess any pressure signal received from the pressuresensor to determine if it has one or more attributes consistent withthose of a valid hemodynamic pressure signal (e.g., a specificamplitude, a specific periodicity, etc.). If the hemodynamic pressuresignal is no longer present, the controller may refrain from adding thequantity of dispensed fluid to the counted quantity 418. If, on theother hand, the hemodynamic pressure signal is still present, thecontroller may add the quantity of dispensed fluid to the countedquantity 430. In some embodiments, as discussed elsewhere herein, thecontroller may be configured to compare the counted quantity with apredetermined threshold and to notify the user if the counted quantityexceeds the threshold 432.

Non-transitory computer-readable storage article embodiments can also beused for any of the methods discussed herein (e.g., quantifying how muchfluid is delivered into a patient by a powered fluid injector). Invarious embodiments of such a non-transitory computer-readable storagearticle, one or more of the details provided above in reference to anyof the figures can be implemented in computer-executable instructionsstored on the non-transitory computer-readable storage article. It is tobe understood that the term “non-transitory,” as used herein, is alimitation of the medium itself (e.g., tangible, not a signal) asopposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

Various examples have been described with reference to certain disclosedembodiments. The embodiments are presented for purposes of illustrationand not limitation. One skilled in the art will appreciate that variouschanges, adaptations, and modifications can be made without departingfrom the scope of the invention.

1. A system comprising: a powered fluid injector; a catheter fluidlyconnectable to the powered fluid injector, the catheter including aninvasive blood pressure sensor that is configured to provide ahemodynamic pressure signal only when the catheter is inside a patient'svasculature and in fluidic connection with a pressure transducer that isconnected to the powered fluid injector; and a controller configured to:receive a command from a user to begin dispensing contrast fluid;determine whether the hemodynamic pressure signal is present from theinvasive blood pressure sensor; cause the powered fluid injector todispense a quantity of contrast fluid in response to the command; addthe quantity of contrast fluid to an injection quantity if thehemodynamic pressure signal is present in temporal proximity to when thequantity of contrast fluid is dispensed; and refrain from adding thequantity of contrast fluid to the injection quantity if the hemodynamicpressure signal is not present in temporal proximity to when thequantity of contrast fluid is dispensed.
 2. The system of claim 1,wherein the controller is configured to determine whether thehemodynamic pressure signal is present by determining whether thehemodynamic pressure signal is present within a predetermined amount oftime before the controller causes the powered fluid injector to begindispensing the quantity of contrast fluid.
 3. The system of claim 2,wherein the controller is configured to determine whether thehemodynamic pressure signal is present by further determining whetherthe hemodynamic pressure signal is present within a predetermined amountof time of the controller causing the powered fluid injector to ceasedispensing the quantity of contrast fluid.
 4. The system of claim 1,wherein the controller is configured to determine whether thehemodynamic pressure signal is present by determining whether thehemodynamic pressure signal is present within a predetermined amount oftime of the controller causing the powered fluid injector to ceasedispensing the quantity of contrast fluid.
 5. The system of claim 1,wherein the catheter comprises a guide catheter.
 6. The system of claim1, wherein the catheter comprises a diagnostic catheter.
 7. The systemof claim 1, wherein the controller is further configured to notify theuser if the injection quantity exceeds a threshold.
 8. The system ofclaim 1, wherein the controller is further configured to: receive asecond command from the user to begin dispensing non-contrast fluid;cause the powered fluid injector to dispense a quantity of non-contrastfluid in response to the second command; add the quantity ofnon-contrast fluid to a dispensed quantity if the hemodynamic pressuresignal is present in temporal proximity to when the quantity ofnon-contrast fluid is dispensed; and refrain from adding the quantity ofnon-contrast fluid to the dispensed quantity if the hemodynamic pressuresignal is not present in temporal proximity to when the quantity ofnon-contrast fluid is dispensed.
 9. The system of claim 1, wherein thecontroller is configured to determine whether the hemodynamic pressuresignal is present by assessing a pressure signal from the invasive bloodpressure sensor to determine whether the pressure signal constitutes avalid hemodynamic pressure signal.
 10. The system of claim 9, whereinassessing the pressure signal comprises assessing an amplitude and/or aperiodicity of the pressure signal.
 11. A system comprising: a poweredfluid injector; a catheter fluidly connectable to the powered fluidinjector, the catheter including an invasive blood pressure sensor thatis configured to provide a hemodynamic pressure signal only when thecatheter is inside a patient's vasculature and in fluidic connectionwith a pressure transducer that is connected to the powered fluidinjector; and a controller configured to: receive a command from a userto begin dispensing contrast fluid; determine whether the hemodynamicpressure signal is present from the invasive blood pressure sensor; andtake an injection action only if the hemodynamic pressure signal ispresent from the invasive blood pressure sensor.
 12. The system of claim11, wherein the injection action comprises: causing the powered fluidinjector to dispense a quantity of contrast fluid in response to thecommand; and adding the quantity of contrast fluid to an injectionquantity if the hemodynamic pressure signal is present in temporalproximity to when the quantity of contrast fluid is dispensed.
 13. Thesystem of claim 12, wherein the controller is further configured todetermine whether the hemodynamic pressure signal is present from theinvasive blood pressure sensor after the powered fluid injector hasdispensed the quantity of contrast fluid, and wherein the injectionaction further comprises adding the quantity of contrast fluid to theinjection quantity only if the hemodynamic pressure signal is presentboth before the quantity of contrast fluid is dispensed and after thequantity of contrast fluid is dispensed.
 14. The system of claim 12,wherein the controller is further configured to notify the user if theinjection quantity exceeds a threshold.
 15. The system of claim 11,wherein the powered fluid injector comprises an air bubble detectorconfigured to detect an air bubble in tubing connectable to thecatheter, wherein the controller is further configured to receive an airbubble signal from the air bubble detector that the air bubble has beendetected, and wherein the injection action comprises preventing thepowered fluid injector from dispensing contrast fluid based on the airbubble.
 16. The system of claim 15, wherein, after preventing thepowered fluid injector from dispensing contrast fluid based on the airbubble, the controller is further configured to: receive a secondcommand from the user to begin dispensing contrast fluid, determineagain whether the hemodynamic pressure signal is present from theinvasive blood pressure sensor, and cause the powered fluid injector todispense a quantity of contrast fluid to purge the air bubble inresponse to the second command only if the hemodynamic pressure signalis no longer present from the invasive blood pressure sensor.
 17. Thesystem of claim 15, wherein the controller is further configured tonotify the user that he/she is attempting to purge the air bubble whilethe catheter is inside a patient's vasculature and in fluidic connectionwith the pressure transducer.
 18. A method for quantifying how muchcontrast fluid is injected into a patient by a powered fluid injector,comprising: receiving, at a controller of the powered fluid injector, acommand from a user to begin dispensing contrast fluid; determining,with the controller, whether a hemodynamic pressure signal is presentfrom a pressure sensor positioned in fluidic connection with thepatient's vasculature; dispensing, with the powered fluid injector, aquantity of contrast fluid in response to the command; adding, with thecontroller, the quantity of contrast fluid to an injection quantity ifthe hemodynamic pressure signal is present in temporal proximity to whenthe quantity of contrast fluid is dispensed; and refraining from adding,with the controller, the quantity of contrast fluid to the injectionquantity if the hemodynamic pressure signal is not present in temporalproximity to when the quantity of contrast fluid is dispensed.
 19. Themethod of claim 18, wherein determining, with the controller, whetherthe hemodynamic pressure signal is present includes determining, withthe controller, whether the hemodynamic pressure signal is presentwithin a predetermined amount of time before the powered fluid injectorbegins dispensing the quantity of contrast fluid.
 20. The method ofclaim 19, wherein determining, with the controller, whether thehemodynamic pressure signal is present further includes determining,with the controller, whether the hemodynamic pressure signal is presentwithin a predetermined amount of time of the powered fluid injectorcompleting dispensing of the quantity of contrast fluid.
 21. The methodof claim 18, wherein determining, with the controller, whether thehemodynamic pressure signal is present includes determining, with thecontroller, whether the hemodynamic pressure signal is present within apredetermined amount of time of the powered fluid injector completingdispensing of the quantity of contrast fluid.
 22. The method of claim18, further comprising providing a notification if the injectionquantity exceeds a predetermined threshold.
 23. The method of claim 18,further comprising assessing, with the controller, a pressure signalreceived from the pressure sensor to determine whether the pressuresignal constitutes a valid hemodynamic pressure signal.